How does this medication work? What will it do for me?

This combination medication contains peginterferon alfa-2b and ribavirin. Peginterferon alfa-2b belongs to the group of medications known as interferons and ribavirin belongs to the group of medications known as antivirals. It is used to treat chronic hepatitis C (a disease of the liver). It works by helping the immune system fight the hepatitis C virus, and by making it harder for the virus to reproduce within the body.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. As well, some forms of this medication may not be used for all of the conditions discussed here. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

What form(s) does this medication come in?

Capsules
Each opaque, white, hard gelatin capsule, filled with a white powder and printed with the Schering-Plough logo and "200 mg" in blue ink, contains ribavirin 200 mg. Nonmedicinal ingredients: croscarmellose sodium, lactose monohydrate, magnesium stearate, and microcrystalline cellulose; capsule shell: gelatin, silicon dioxide, sodium lauryl sulfate, and titanium dioxide.

Powder for solution
Each single-dose vial of white powder contains peginterferon alfa-2b 74 µg or 222 µg and delivers 50 µg and 150 µg in 0.5 mL of reconstituted solution respectively. Nonmedicinal ingredients: polysorbate 80, sodium phosphate dibasic anhydrous, sodium phosphate monobasic dihydrate, and sucrose.

Powder for solution in RediPen Delivery System
Pegetron Redipen Single-Dose Delivery System consists of a dual chamber glass cartridge with a chamber containing peinterferon as a white to off white lyophilized powder and another chamber containing sterile water for injection. The cartridge is provided in a pen device for reconstitution, dose preparation, and subcutaneous administration, to deliver doses of 80, 100, 120 or 150 µg in 0.5 mL of reconstituted solution. Each Redipen contains 108, 135, 162 or 202.5 µg of peginterferon alfa-2b. Following reconstitution of the powder with the diluent contained within the cartridge, each Redipen gives a final volume of 0.675 mL for administration of up to 0.5 mL. The reconstituted solution contains 160, 200, 240, 300 µg/mL respectively. Nonmedicinal ingredients: sodium phosphate dibasic anhydrous, sodium phosphate monobasic dihydrate, sucrose, and polysorbate 80.

How should I use this medication?

This medication is available as a package containing ribavirin capsules and peginterferon alfa-2b injections. The ribavirin capsules are taken by mouth in combination with the peginterferon alfa-2b injections.

Capsules: The capsules are taken by mouth twice daily (morning and evening) with food. Dosing is based on body weight.

Injection: The injection is injected subcutaneously (under the skin) once weekly on the same day of the week. Dosing is based on body weight.

The doses of these medications may vary depending on whether this is the first time you have been prescribed peginterferon alfa-2b - ribavirin and the strain of hepatitis C virus being treated.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

Peginterferon alfa-2b - ribavirin is used with the guidance and supervision of a doctor. Your doctor or nurse will assist you in the preparation and injection of your first dose (or first few doses). Do not attempt to inject this medication on your own until you completely understand how to inject a dose. If you are unsure of how to prepare or administer a dose, ask a health care professional to help you.

Before injecting the prepared medication, check the solution to ensure that it is clear, colourless, and completely dissolved. After the medication has been mixed it should be used right away.

It is important to take this medication exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication in the refrigerator at 2°C to 8°C and keep it out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Who should NOT take this medication?

Do not use this medication if you:

  • are allergic to peginterferon alfa-2b, ribavirin, or any ingredients of the medication
  • are allergic to any other interferon
  • are pregnant or are a man whose female partner is pregnant
  • have decompensated liver disease
  • have epilepsy
  • have or have had autoimmune diseases (including autoimmune hepatitis)
  • have severe psychiatric conditions or a history of severe psychiatric disorder
  • have severely reduced kidney function
  • have uncontrolled thyroid disorders

What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

  • aching, fullness, or tension in sinuses
  • constipation
  • cough
  • diarrhea
  • difficulty sleeping
  • dizziness or lightheadedness
  • dry mouth
  • dry skin
  • flu-like symptoms (e.g., chills, fatigue, fever, sore throat, stuffy or runny nose)
  • hair loss (temporary)
  • headache (mild)
  • injection site reaction, pain, or inflammation
  • muscle soreness
  • nausea
  • pain in joints or muscles
  • rash
  • vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

  • abdominal bloating or gas
  • abdominal pain
  • aggressive behaviour
  • anxiety
  • confusion
  • decreased memory
  • difficulty concentrating
  • flushing of the skin
  • hallucination
  • headache (severe)
  • hearing loss
  • heartburn
  • increased sweating
  • increased thirst
  • irregular menstrual bleeding
  • irritability
  • itching, redness, or swelling of eyes
  • loss of appetite
  • low or high blood pressure
  • migraine
  • mood swings
  • muscle spasms or stiffness
  • nervousness
  • numbness or tingling in the extremities
  • ringing in the ears
  • signs of depression such as:
    • changes in sleep
    • changes in weight
    • decreased interest in activities
    • poor concentration
    • thoughts of suicide
  • signs of heart problems such as:
    • chest pain
    • difficulty breathing
    • fast or irregular heartbeat
    • swelling of the feet, ankles, or lower leg
    • unusual tiredness or weakness
 
  • signs of infection such as:
    • fever or chills
    • headache
    • listlessness
    • prolonged dizziness
    • severe diarrhea
    • shortness of breath
    • stiff neck
    • weight loss
  • signs of kidney problems such as:
    • decreased urine production
    • difficulty urinating
    • painful urination
  • signs of liver problems such as:
    • dark urine
    • diarrhea
    • loss of appetite
    • nausea
    • pale stools
    • vomiting
    • weight loss
    • yellowing of the skin or whites of the eyes
  • signs of unusual bleeding such as:
    • bleeding gums
    • blood in urine
    • bloody, black, or tarry stools
    • bloody diarrhea
    • pinpoint-sized red spots on skin
    • spitting up of blood
    • unusual bruising or cuts that don't stop bleeding
    • vomiting blood or material that looks like coffee grounds
  • skin rash
  • skin sensitivity to sunlight or skin rash
  • tremor
  • vision changes including blurred vision
  • weight loss

Stop taking the medication and seek immediate medical attention if any of the following occur:

  • convulsions (seizures)
  • signs of a serious allergic reaction such as:
    • difficulty breathing
    • hives
    • swelling of the face or throat
  • signs of a severe skin reaction such as:
    • a rash combined with fever or discomfort
    • a rash covering a large area of the body
    • a rash that spreads quickly
    • blistering
    • peeling
  • signs of pancreatitis such as:
    • abdominal pain on the upper left side
    • back pain
    • chills
    • fever
    • nausea
    • rapid heartbeat
    • swollen abdomen

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Allergic reaction: In rare cases, this medication may cause severe allergic reaction. If you notice hives, swelling of the face or throat, or difficulty breathing, stop using this medication and get medical help immediately.

Blood disorders: Ribavirin can cause severe anemia (low level of red blood cells). Anyone taking this medication should have regular blood tests done by their doctor. People with blood disorders such as sickle-cell anemia or thalassemia should not use this medication.

Colitis: There is a risk of developing serious forms of colitis with peginterferon treatment. The symptoms resolve when peginterferon treatment is stopped. If you experience symptoms of colitis such as abdominal pain, bloody diarrhea, and fever, contact your doctor immediately.

Depression and other psychiatric disorders: Peginterferon alfa-2b has been known to cause symptoms of depression and other psychiatric disorders. If you have depression or a history of depression, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. If you experience symptoms of depression such as poor concentration, changes in weight, changes in sleep, decreased interest in activities, or notice them in a family member who is taking this medication contact your doctor as soon as possible.

People with pre-existing psychiatric conditions or a history of a severe psychiatric disorder should not take this medication, as it may worsen these conditions. If you feel depressed, aggressive, or suicidal, or if you have hallucinations, stop using this medication and contact your doctor as soon as possible.

Diabetes: Peginterferon alfa-2b may cause an increase in blood sugar levels and glucose tolerance may change. People with diabetes may find it necessary to monitor their blood sugar more frequently while using this medication.

If you have diabetes or are at risk for developing diabetes, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Drowsiness/reduced alertness: This medication may cause drowsiness or confusion. If the medication affects you in this way, avoid driving, operating machinery, or other tasks that require alertness until you know how this medication affects you.

Fertility: This medication may impair fertility in men and women.

Flu-like symptoms: Peginterferon alfa-2b may cause a flu-like reaction, with aching muscles, fever, chills, and headache. Your doctor may prescribe acetaminophen before each dose of peginterferon alfa-2b and as needed to help reduce these symptoms.

Fluids: This medication may cause dehydration, which can lead to side effects such as dizziness, and in severe cases, kidney problems. People taking this medication should drink adequate fluids, especially on hot days or when exercising.

Heart disease: People who have had a heart attack, heart disease, or changes in heart rhythm (arrhythmias) should discuss with their doctor how this medication may affect their medical condition, how their medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

This medication may cause heart problems for people who have not had heart problems in the past. If you experience symptoms such as chest pain or pressure, difficulty breathing, pounding or irregular heart beat, contact your doctor immediately.

Infection with HIV or hepatitis B: The safety and efficacy of treatment with peginterferon alfa-2b - ribavirin has not been established for people who have hepatitis C co-infected with human immunodeficiency virus (HIV) or hepatitis B virus (HBV).

Kidney disease: If you have kidney disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. People with severely reduced kidney function should not use this medication.

Liver function: Peginterferon alfa-2b can cause decreased liver function. Your doctor will order blood tests check your liver function. If you have liver problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

If you experience signs of decreased liver function such as pale stools, dark urine, yellowing of the skin or eyes, contact your doctor as soon as possible.

Oral health: This medication can cause dry mouth, which may lead to dental disease. Good oral hygiene, including regular brushing and flossing, should be practiced while using peginterferon alfa-2b - ribavirin.

Organ transplantation: The safety and efficacy of peginterferon alfa-2b - ribavirin treatment has not been established for patients with liver or other organ transplants. There is a possibility that this medication may cause organ rejection.

Other medical conditions: This medication may cause or worsen autoimmune disorders, infections, thyroid changes, lung problems, diabetes, high cholesterol levels (specifically triglycerides), eye disorders, and circulation problems. People with these conditions should discuss with their doctor how this medication may affect their medical condition, how their medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Pancreatitis: Interferon treatment can cause serious forms of pancreatitis (inflammation of the pancreas). If you have a history of or are at risk for developing pancreatitis, you should be closely monitored by your doctor while taking this medication. If you develop signs of pancreatitis (e.g., upper left abdominal pain, back pain, nausea, fever, chills, rapid heartbeat, swollen abdomen), contact your doctor.

Response to therapy: People who have used peginterferon and ribavirin in the past or those who have not responded to treatment with interferon and ribavirin in the past are less likely to benefit from using this product. Cirrhosis or fibrosis of the liver, as well as infection with hepatitis C virus (specifically genotype 1) are also less likely to respond to this medication.

Vision changes: Rarely, this medication can cause vision problems, such as loss of acuity or visual field. People taking this medication should have regular eye examinations and report any changes in vision to their doctor immediately.

Pregnancy: Peginterferon alfa-2b has not been studied for use by pregnant women. Ribavirin has been shown to cause serious problems in the developing fetus. The combination of peginterferon alfa-2b and ribavirin should not be used by pregnant women or by men whose partners are pregnant. Both partners should use a reliable form of birth control while taking this medication and for 6 months afterwards (the time it takes for ribavirin to be cleared from the body). Tell your doctor immediately if you become pregnant while using this medication.

Breast-feeding: It is not known if peginterferon alfa-2b or ribavirin pass into breast milk. Because side effects of this medication could be harmful to the baby, women should not breast-feed while using this medication.

Children and adolescents: The safety and effectiveness of using this medication have not been established for children and adolescents under 18 years of age.

What other drugs could interact with this medication?

There may be an interaction between peginterferon alfa-2b - ribavirin and any of the following:

  • aldesleukin
  • azathioprine
  • influenza vaccines
  • reverse transcriptase inhibitors; anti-HIV treatment (abacavir, didanosine, entecavir, lamivudine, stavudine, zidovudine)
  • telbivudine
  • theophylline

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

  • stop taking one of the medications,
  • change one of the medications to another,
  • change how you are taking one or both of the medications, or
  • leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.